<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<style type="text/css">
			/*
			选择器的优先级
			
			默认<通配符<标签<类 < id  <  行内  < !important
			0      1    10  100 1000   10000    无穷大
			*/
		   /*3100*/
		   #box1>.box2>#box3>#box4{
			   color: green!important;
		   }
		</style>
	</head>
	<body>
		<div id="box1">
			<div class="box2">
				<div id="box3">
					<div id="box4" style="color: red;">box4</div>
				</div>
			</div>
		</div>
	</body>
</html>
